There is a continued need for medication packages that are child resistant and tamper evident, yet allow the average adult to open the medication packages to get access to the medication therein. There is also a need to make this type of package economical to manufacture.
In the past, there have been a number of different medication packages developed. Many of the packages have a top layer with blisters to hold the medication and a bottom layer sealed to the top layer to enclose the medication in the blister. In some instances, the bottom layer is made of foil that can be ruptured when the medication in the blister is pushed against the bottom layer. This is tamper evident but typically not child resistant. Other medication packages require some form of peeling the bottom surface from the top surface to get access to the medication. Some examples of these types of medication packages that use peeling include U.S. Pat. Nos. Re 29,705 (Compere), 3,941,248 (Moser), 4,243,144 (Margulies), 4,988,004 (Intini), 5,046,618 (Wood), and 5,358,118 (Thompson). Child resistant medication packages that use peeling have been in use for some time, however, some people who do not have sufficient motor skills or whose hands shake are not able to easily gain access to the medicament is such packages. This can be a problem especially when the medicament and the medication packages are small.
There have been a number of medication packages that are designed to be torn open to access the medication. One patent that discloses a tear-open package does not relate to medication packages, but instead relates to a rigid, fluid-tight, hand fracturable container for protecting O-rings and other small rubber or synthetic plastic parts from deterioration and deformation, is U.S. Pat. No. 3,456,784 (Sirago). The figures showing a plan view in this Pat. No. 3,456,784 look similar to what a plan view of the present invention may look like. However, a closer analysis of the text and figures of U.S. Pat. No. 3,456,784 shows that the invention disclosed in U.S. Pat. No. 3,456,784 actually teaches away from the present invention disclosed below. U.S. Pat. No. 3,456,784 discloses weakened fracture lines that are formed by "fusing" the first panel to the second panel (see col. 1, lines 66-68, col. 3, lines 27-29, and col. 4, lines 22-25). Unlike U.S. Pat. No. 3,456,784, the present invention has tearing blisters formed in the blister layer and the blister layer is not joined to the base layer in the areas of the tearing blisters. Therefore, instead of fusing the first panel and second panel together to form a weakened fracture line, the present invention does the opposite by not fusing the blister layer and the base layer together at the tearing blisters. In fact, in accordance with the present invention, the blister layer and the base layer are not even sealed together at the tearing blisters.
U.S. Pat. No. 5,088,603 (Kirkpatrick) discloses a tear-open medication package that has a tear slit disposed through the package directed at one end of the blister containing the medicament. The tear slit is a cut or perforation through the entire package (i.e., the blister layer and the base layer). The use of a tear slit attempts to make the medication package easier to tear open the package, but in practice these packages (e.g., used for Tylenol Cold.RTM.) can still be difficult to open by an adult. There is a need for a medication package that can be relatively easy to tear for an adult, but still be child resistant.
The present invention provides a novel blister package for use with small or large medicaments of various shapes. The present invention discloses a blister package that implements tearing to be opened, thereby avoiding some of the inherent problems of medication packages that use peeling to be opened. The blister package of the present invention can be relatively easy to tear for an adult, but not easy for a child to access a medicament within the package. The present invention is economical to make because it uses tear blisters that are formed in the same manner as the article receiving blisters therein.
The blister package of the present invention comprises a blister layer having an article receiving blister formed therein for holding medicaments, and a base layer. The blister layer has one or more tearing blisters formed therein and the blister layer is joined to the base layer except in the areas of the article receiving blister and the tearing blisters. The base layer and the blister layer are joined such that opening the blister package to access the medicament requires tearing through one of the tearing blisters and the article receiving blister. The tearing blisters preferably extend from one or more outer edges, which may include the corners, of the blister layer toward said article receiving blister. The portions of the base layer and the blister layer that are joined together cannot be readily torn from the outer edges of the blister package, but the portion of the blister layer that forms the tearing blister is thin enough that the tearing blister and the portion of the base layer under the tearing blister can be readily torn from the outer edge of the blister package.
Another embodiment of the present invention is a medication package comprising a plurality of separable blister packages like those described in the preceding paragraph. These separable blister packages have their base layer and/or blister layer formed from one integral base layer and one integral blister layer with tear lines in the base layer and/or the blister layer to enable the separation of the individual blister packages from each other. These tear lines may be perforations, score lines, slits, weakened fracture lines, and/or even tearing blisters. Another embodiment of the medication package of the present invention includes a separable header portion connected to one or more of the blister packages. The header portion preferably has an area on which drug information, bar codes, etc. can be printed.
Various objects and advantages of the present invention will become apparent from the following detailed description when viewed in conjunction with the accompanying drawings, which set forth certain embodiments of the invention.